羟基增塑剂的羟基数目对淀粉浆料增塑作用的影响

以淀粉浆膜的断裂伸长为评价标准,通过对比试验评价羟基增塑剂对淀粉浆料的增塑作用,从分子结构上认识羟基增塑剂的羟基数目对淀粉浆料增塑作用的影响,并通过浆液特性及黏附性能评估羟基增塑剂正戊醇、正丁醇、1,2-丙二醇、乙二醇、甘油、1,1,1-三羟甲基丙烷、季戊四醇、木糖醇及山梨醇的使用效果.研究结果表明:羟基增塑剂对淀粉浆料都具有增塑作用,能够改善淀粉浆膜脆而硬的缺陷.随着增塑剂羟基数目的增加,淀粉浆膜的断裂伸长率逐渐增大;在羟基数目为3时,增塑作用达到最大;但进一步增加羟基数目,增塑作用下降.在所研究的羟基增塑剂中,甘油和1,1,1-三羟甲基丙烷的增塑作用效果最明显,以其作为淀粉浆料的增塑剂,可以减少浆纱和织造落物,提高织造效果.

Effect of Hydroxyl Number of Hydroxyl-Containing Plasticizers on Their Plasticization for Starch Sizing Agents

In order to reveal the influence of number of hydroxyls in molecules of hydroxyl-containing plasticizers on the plasticization for starch sizing agents,plasticization of the plasticizers was investigated through contrast test.The plasticization was evaluated in terms of extension and tensile strength of starch film.And end-use ability of the plasticizers was accessed through film performances,adhesion-to-fibers,and paste behaviors(viscosity and its stability).The plasticizers evaluated included n-amyl alcohol,n-butyl alcohol,1,2-propylene glycol,glycol,glycerol,1,1,1-trimethylolpropane,pentaerythritol,xylitol,and sorbic alcohol.Experimental results demonstrated that all the plasticizers exhibited plasticization for starch sizing agents,and could reduce the shortcomings such as film rigidity and brittleness of starch.The plasticizers enhanced the plasticization of starch with increasing the number of hydroxyls up to 3,reaching maximal effect,and beyond this number it reduced again.Glycerol and 1,1,1-trimethylolpropane showed the most marked plasticization for plasticizing starch sizing agents among the plasticizers considered.For this reason,these two plasticizers were recommended in uses for reducing shedding of size and lint in sizing and weaving operations so as to improve weaving efficiency.